Campbell is most famous for whitewashing Stephen Hendry 9–0 in the 1998 Liverpool Victoria UK Championship, one of the most surprising results in snooker's history.

He started the 2007/2008 season strongly by reaching the last 16 of the Grand Prix, coming through the qualifiers and beating players like Graeme Dott and Anthony Hamilton before his run ended in a 5–2 defeat to Joe Swail.

Liang had time to compose himself and won the decider to end Campbell's season, which he finished ranked world number 25.

[6][7] The 2012–13 season began very well for Campbell as he qualified for the Wuxi Classic, where he reached the first ranking event semi-final of his 21-year professional career.

[9] He had his best run of the season since Wuxi at the China Open where he overcame Peter Ebdon 5–3 and Graeme Dott 5–4 to make the quarter-finals.

[9] Campbell qualified for the World Championship with a 10–4 victory against Liam Highfield and played defending champion Ronnie O'Sullivan in the first round, who had taken a year away from snooker since lifting the title 12 months previously.

[15] Campbell could not advance beyond the first round in any of the remaining ranking events and suffered a surprise 10–4 defeat to Alex Borg in World Championship qualifying, a player who had until then only won three matches all season.